Equalizing device



June 6, 1933. 5 J. MORAN 1,912,537

EQUALI Z ING DEVICE Filed Aug. 2, 1930 l u f .30 3/ Jo .3/ J0 J/ /7 as as" .53 23 .33"

fly-cams latented june 6, 1933 UNITED STATE S,

SAMUEL J. MORAN, OF LOS ANGELES, CALIFORNIA EQUALIZIN G DEVICE Application filed- August 2, 1930. SeriaLNo. 472,622.

This invention relates in a general way to a device for equalizing the strain in. a plurality of correlated tension members. The devicecontemplated by this invention has been. developed. especially for use in connection with elevators. It is to be understood, however, that the invention is not in any way confined to this particular field of use, butmaybeemployed any place whereunlt-ary fotce. is applied to an object through a plurality of members, the purpose of the devlce being.- to automatically maintain an equal distribution of the force. among the various members.

It well known that when a unitary tensil force is applied to an object through a plurality of members, such as cables, that one of these members may have a tendency to stretch and that such stretching action throws nearly all of the load upon the other members It is the primary object of this invention to produce a device which may be employed in attaching members of the class referred to above, to the object, such device being constructed so as to efiect an automatic adjustment in the length of the members which will bring about an equalization of forces among the variousmembers.

, As pointed out above, the invention has been developed primarily for use in connection with elevators. It is well known to those familiar with the art that the usual construction employed in elevators consists of a cage which is suspended in the elevator shaft by a. plurality of cables, such cables running over a power drum in the top of the shaft andextending downwardly through the shaft to form loops having their lower end portions attached to the bottom of the cage, Counterweights are of course attached toQt-he. cables, at their intermediate portions. Instructures of this nature it has been found that after a comparatively brief period of use one or more of the cables has a tendency to stretch. This-throws practically the entire load of the cage upon the other cables and to compensate for this stretching actionthe cables are usually attached to the top of the cage through the medium; of turn best of my knowledge no such device has been."

buckles. or other similar adjustable connection. i

It has been found practically impossible to maintain uniform tension in the cables through the use of manual. adjustments of the type referred to above. Numerous at-. tempts have. been made to perfect an attach-.. ing member for. use in connecting cables of this nature to the elevator cage which will automatically maintain an equalstrain in all of the tension members. Most of the efforts with which I am familiar directed toward the production of'a device of thischaracter, have been through the use of hydraulics, and to the perfected which is practical. A slight leak in one of the glands. through which the cable or the. cable attaching bar extends rendersthe unit inoperative in a very short time.

It is a further object of this invention to 7051 produce an equalizing device of theclass described which contains a non-fluid equalizing medium. The general construction of the device contemplated by this invention consists of a housing provided with a chamber containing a plurality of plunger members Each of the plunger members is attached to.

one of the tension members and the chamber is filled with a yieldable non-fluid medium,

which in the preferred form of my invention consists of a body of metal spheres or ball bearings.

In addition to thestretching action which occurs in the cables of the general type re-- ferred to, above, there is also a tendency. for these cables to unwind during theircontinueduse, and it is a noteworthy feature of this invention that I have provided additional means for preventing relative rotating movement between the cable and the point of connection to the suspended object.

The details in the construction ofa preferred form of my invention, together with other obj eets attending its production, will be best understood from the following description of the accompanying drawing, which is chosen for illustrative purposes only, and.

in which Fig. 1 is a diagrammatic view showing the manner in which the device contemplated by this invention may be employed in connection with an elevator;

Fig. 2 is a sectional elevation which may be considered as having been taken in a plane represented by the line 22 in Fig. 1;

Fig. 3 is an enlarged sectional elevation taken in a plane represented by the line 33 in Fig. 1;- D

Fig. 4 is a broken plan section taken n planes represented by the broken line 4-4: in F i 3.

is pointed out above, the device contemplated by this invention is adapted for numerous uses other than the one specific use for which it was developed, but for the purpose of clarity in describing the invention, I have shown the same in connection with an elevator.

-Referring now to Fig. 1, reference numeral. 11 indicates an elevator cage which consists of upright members 12 and 13, a base member 14, and a top or ceiling member 15. The ceiling member 15 embodies a central beam or housing 17 which forms a part of the device contemplated by this invention.

The cage 11 is suspended in the elevator shaft from a plurality of cables, indicated by reference numeral 18. Such cables run over a power drum 19' and a take-up drum 20, and extend downwardly through the elevator shaft where they are attached to a counterweight 21 and where they form loops 22, having their. bottom end portions 23 attached to the bottom of the cage.

The details in the construction of the equalizing device contemplated by this invention, are best illustrated in Figs. 2 to {t inclusive, where the beam or housing 17 is shown as embodying two interfitting members 25 and 26 connected together through the medium of bolts 27. t The member 26 isprovided with a recess 28 which forms a chamber in the housing 17 and the member 25 is provided with a plurality of recesses 29a,'29?), and 290, which communicate with the chamber 28 to form what will hereinafter be referred to as plunger recesses. The upper edges of the recesses 29a, 29b, and 290, are shown as being rounded as indicated at 30, and the bottom portions of these recesses are provided with vent apertures 31. Itwill be understood, of course, that the particular manner of forming the housing 17 may be varied without departing from the scope of this invention, the two piece housing provided with this particular form of recessed construction being chosen merely because of its simplicity.

The top portion of the upper section 26 is provided with a plurality of apertures 32a,

to the lower end portions of tension rods 34a, 34b, and 340. The tension rods 34a, 34b, and 340, have their upper end portions attached to the cables 18a, 81b, and 180.

It was pointed out above that means were provided in this device for preventing relative rotative movement between the cables and the housing or beam 17. This is accomplished by making each of the members 34a, 34b, and 8410, square or polygonal in shape and making the apertures 32a, 32b, and 320, of corresponding shape.

Reference numeral 35 indicates a body of metal spheres which is contained within the chamber 28 above the plungers 83a, 33b, and 380, and which will hereinafter be referred to as comprising a yieldable nonfluid medium. These spheres may be lubricated in any suitable manner, such as by means of graphite, and it will be apparent that they will always adjust themselves so that the thrust which is transmitted to the plungers from the tension members 3%, 34b, and 340, and which is applied from the upper surface of the plungers to the spheres in contact therewith, will beequally distributed'among the various tension members.

member 34?), stretches a slight distance, menr here 3464 and 346 will immediately take the additional load given up through the stretching of the cable. By taking this load they will exert an additional upward thrust component upon the body of spheres, which will be transmitted through this body and will act downwardly upon the plunger 33b, moving the same downwardly until the tension in all of the members is again equal.

cost.

In other words, if the cable 18b, for example, which is connected to the It will be apparent from the foregoing de-v i scription that the device contemplated by this invention is of simple form and construction, the devices does not require theme of fluid tight packing which must be continually watched; it does not necessitate frequent manual adjustment in the way of tightening packing glands or taking up turn buckles and it may be economically manufacturedand quickly installed upon any device wherein a unitary force is applied to an object through a plurality of members.

It is to be understood that while I have herein described and illustrated one pre-' ferred form of my invention and have shown the same as being applied to one particular use, the invention is not limited to the precise construction described above, but includes within its scope whatever changes fairly come within the spirit of the appended claims.

I claim as my lnvention:

1. A device for equalizing the strain in a plurality of tension members embodying: a

housing having a chamber therein adapted to receive the end portions of said tension members; plungers attached to said tension members in said chamber, and a body of metal spheres filling the space in said chamber above said plungers.

2. A device for equalizing the strain in a plurality of tension members embodying: a housing having a chamber therein adapted to receive the end portions of said tension members; plungers attached to said tension members in said chamber, and a body of metal spheres filling the space in said chamber above said plungers and arranged to receive the thrust from all of said plungers when said tension members are under tension.

3. A device for equalizing the strain in a plurality of tension members embodying: a housing provided With a chamber having a plurality of plunger receiving recesses therein; plungers in said recesses; tension members attached to said plungers and extending through said chamber; and a body of metal spheres filling the space in said chamber above said plungers for receiving the thrust applied to said plungers through said tension members. A

4:. A device for equalizing the strain in a plurality of tension members embodying: a housing provided with a chamber having a plurality of plunger receiving recesses therein; plungers in said recesses; said housing being provided with apertures extending into said chamber opposite said plunger receiving recesses; tension members attached to said plungers and extending through said apertures; and a body of metal spheres filling the space in said chamber above said plungers for receiving the thrust applied to said plungers through said tensionmembers.

5. For use in supporting a suspended object: a plurality of tension members; and means for attaching said members to said object comprising a housing on said object hav ing a chamber therein, plungers in the bottom of said chamber, said plungers being attached to said tension members, and a body of metal spheres in said chamber above said plungers.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 22 day of July, 1930.

SAMUEL J. MORAN. 

